JPH0552955A - Infrared rays image device - Google Patents

Abstract

PURPOSE:To enable electromagnetic interference from a distance-measuring equipment for an infrared ray image to be eliminated by providing a control portion which generates a blanking signal representing the ineffective period of a scanning command based on a reference signal from an optical control portion which gives the scanning command to an optical system which detects infrared rays and a discharge standby means for achieving a temporary standby of a laser discharge command. CONSTITUTION:An emission standby means 4 is constituted by an AND gate 42 where an output of a register 41 and a blanking signal which is generated by a control portion 10 based on a reference signal of an optical control portion 3 are input and latch circuits 43-45 which latch the signal in sequence. An emission command of the register 41 is given to a latch circuit 43 only when the blanking signal is given to the AND gate 42 and is delayed by a certain period by a synchronization clock from a timing generator 8 and then is fed to a distance-measuring equipment 1. An image signal during the blanking signal period is masked by a data signal processing portion 7, thus preventing an influence of electromagnetic interference from appearing as an infrared ray image.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an infrared imager,
In particular, the present invention relates to an infrared imaging device arranged at a distance close to a laser range finder.

In recent observation systems, particularly when mounted on an aircraft or the like, space is limited, so it is necessary to install a plurality of devices in the same space, and a laser range finder and an infrared imaging device are required. It is often installed in close proximity.

[0003]

2. Description of the Related Art FIG. 4 schematically shows a so-called space stabilizer 30 in which such a laser range finder 1, an infrared imager 21 and a visible imager 22 are arranged in the same space. In the above, the visible image is obtained by the visible image device 22 and the infrared image is obtained by the infrared image device 10 at night.

The distance to the object is measured by the laser light emitted from the laser range finder 1 both in the daytime and the nighttime.

[0005]

However, since such a laser range finder 1 consumes a large amount of power and generates EMI (electromagnetic interference), the laser range finder 1 and other devices are close to each other. When arranged, there is a problem that the infrared imaging device 21 that handles a very small signal is more susceptible to EMI interference from the laser range finder 1 than other devices.

As measures against this EMI, cable shielding and power source strengthening (filtering) can be considered, but it is difficult to completely remove noise, and a lot of time is spent in the test and adjustment stage of equipment. In addition, there is a drawback that the cost becomes high.

Therefore, it is an object of the present invention to completely eliminate EMI from a laser range finder with a simple structure in an infrared imaging device arranged at a distance close to the laser range finder.

[0008]

FIG. 1 shows, in principle, an infrared imaging device 10 according to the present invention for solving the above-mentioned problems. An optical system 2 for detecting infrared light and the optical system 2 for detecting the infrared light are shown. An optical control unit 3 for giving a scanning command to the system 2, a firing standby means 4 for temporarily holding a laser emission command to the laser range finder 1 until receiving the blanking signal, and a reference signal from the optical control unit 3. And a control unit 10 for generating a blanking signal indicating the invalid period of the scanning command.

According to the present invention, in the above structure,
The emission stand-by means 4 can be made to give the laser emission command to the laser range finder 1 at the center of the invalid period by the synchronization clock generated by the control unit 10 from the received signal from the optical system 2.

[0010]

In the present invention shown in FIG. 1, the operation of the laser range finder 1 and the operation of the infrared imager 10 are not independent as in the prior art, but the periods of operation are shifted from each other. Therefore, the influence of the EMI from the laser range finder 1 is to be eliminated.

That is, in the infrared imaging device 10, the optical system 2 for detecting infrared light is normally scan-controlled by a scan command from the optical control section 3, and as shown in FIG. The process of scanning and returning to the origin at a predetermined point (predetermined cycle) is performed.

Of these, what is actually used as the infrared image signal is the period (valid period) shown by the diagonal lines in the figure, and the other periods are invalid periods.
The blanking signal indicating the invalid period is generated from the control unit 3 in the process of generating the scanning signal.

Therefore, the control unit 10 generates this blanking signal on the basis of the reference signal from the optical control unit 3 and supplies it to the firing standby means 4, whereby the firing standby means 4 is supplied.
Is a laser range finder 1 for a laser emission command from an operator only during an invalid period indicated by a blanking signal.
To give to.

As a result, the laser emission command to the laser range finder 1 is waited until the invalid period comes, and the laser range finder 1 emits the laser during the invalid period to measure the distance to the object. It will be possible.

When the laser is emitted during the invalid period of the blanking signal, the optical signal of the optical system 2 is E.
Although the influence of MI is exerted, normally, the video signal during the period of the blanking signal is masked by the signal processing portion in the subsequent stage, so that the influence of EMI does not appear in the infrared image.

[0016]

FIG. 3 shows an embodiment of the infrared imaging apparatus according to the present invention shown in FIG. 1. In this embodiment, the firing standby means 4 has a register 41 for holding a firing command, and An AND gate 42 for inputting the output signal of the register 41 and a blanking signal generated by the control unit 10 based on the reference signal from the optical control unit 3, and the AND gate 42
It is configured by latch circuits 43 to 45 each configured of a D-FF that sequentially latches the two output signals. still,
The register 41 is adapted to be reset by the output signal of the latch circuit 45.

Further, in this embodiment, the control section 10 amplifies the electric signal corresponding to the infrared light detected by the optical system 2 after the optical system 2, and the output signal of the amplifier 5 as a digital signal. A / D converter 6 for converting into a digital signal, and a data signal processing unit (DSP) 7 for digitally processing the output signal of the A / D converter 6 and performing D / A conversion.
And a timing generator 8 for generating the above blanking signal based on a reference signal from the optical control unit 3, and an analog signal output from the DSP 7 is displayed on the monitor 9 as an infrared image. .

Further, the timing generator 8 uses a DSP for synchronizing clocks obtained in the process of digital signal processing.
7 and the latch circuits 43 to 45 in the firing standby means 4.

In the operation of this embodiment, the firing command is first held in the register 41 and then sent to the AND gate 42.

On the other hand, as shown in FIG. 2, when the optical control unit 3 controls the scanning of the optical system 2, a blanking signal indicating the invalid period is generated from the control unit 10 to generate an AN signal.
It is sent to the D gate 42.

Therefore, the firing command from the register 41 is given to the latch circuit 43 only when the blanking signal is given to the AND gate 42, and the three stages of latch circuits 43 to 4 are given by the synchronous clock from the timing generator 8.
It is given to the laser range finder 1 after being delayed by 5 for a certain period.

Since the latch circuits 43 to 45 have a possibility that the EMI failure may remain if the emission command is given to the laser range finder 1 immediately after the invalid period shown in FIG. In order to prevent this, the central time points t1, t2, t3 ,. ． ． The present embodiment employs a three-stage configuration, but the time points t1, t1 at the center from the start point are set.
2, t3 ,. ． ． The number of stages of the latch circuit is determined according to the time until.

Further, when the laser is emitted during the blanking signal invalid period, the video signal of the optical system 2 is affected by EMI, but normally the video signal during the blanking signal period is Since it is masked by the DSP 7 in the latter stage, the infrared image is not affected by EMI.

[0024]

As described above, according to the present invention, the laser emission command to the laser range finder is temporarily held until the blanking signal indicating the invalid period of the scanning command to the optical system for detecting the infrared light is received. With this configuration, it is possible to remove noise due to the influence of EMI on the infrared image at the time of laser emission, and a great effect can be obtained in, for example, an automatic tracking mode triggered by laser distance measurement.

[Brief description of drawings]

FIG. 1 is a block diagram showing in principle an infrared image device according to the present invention.

FIG. 2 is a waveform diagram for explaining the operation of the present invention.

FIG. 3 is a circuit diagram showing an embodiment of an infrared imaging device according to the present invention.

FIG. 4 is a block diagram showing an example of an apparatus including a laser range finder and an infrared imaging apparatus common to the present invention and the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser range finder 2 Optical system 3 Optical control part 4 Emission standby means 7 Digital signal processing part (DSP) 10 Control part In the figure, the same code | symbol shows the same or corresponding part.

Claims (2)

[Claims] 1. An infrared imaging device (10) arranged at a distance close to a laser range finder (1), an optical system (2) for detecting infrared light, and scanning to the optical system (2). A control unit (10) for generating a blanking signal indicating an invalid period of the scanning command based on a reference signal from the optical control unit (3) which gives a command, and an optical control unit (3)
And a standby means (4) for temporarily holding a laser emission command to the laser range finder (1) until it receives the blanking signal.
An infrared imaging device comprising: 2. The infrared imaging device according to claim 1, wherein the emission standby means (4) uses a synchronization clock generated by the control unit (10) from a received signal from the optical system (2). An infrared imaging device characterized in that the laser emission command is given to the laser range finder (1) at the center of the invalid period.